[<prev] [next>] [day] [month] [year] [list]
Message-Id: <20220729061312.2157151-1-zengjx95@gmail.com>
Date: Fri, 29 Jul 2022 14:13:12 +0800
From: Zeng Jingxiang <zengjx95@...il.com>
To: ast@...nel.org, daniel@...earbox.net, john.fastabend@...il.com,
andrii@...nel.org, martin.lau@...ux.dev, song@...nel.org,
yhs@...com, kpsingh@...nel.org, sdf@...gle.com, haoluo@...gle.com,
jolsa@...nel.org
Cc: bpf@...r.kernel.org, linux-kernel@...r.kernel.org,
Zeng Jingxiang <linuszeng@...cent.com>
Subject: [PATCH] bpf/verifier: fix control flow issues in __reg32_bound_s64()
From: Zeng Jingxiang <linuszeng@...cent.com>
expression "a <= S32_MAX" is always true
1580 static bool __reg32_bound_s64(s32 a)
1581 {
1582 return a >= 0;
1583 }
Fixes: e572ff80f05c ("bpf: Make 32->64 bounds propagation slightly more robust")
Signed-off-by: Zeng Jingxiang <linuszeng@...cent.com>
---
kernel/bpf/verifier.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 0efbac0fd126..bd154bcf1599 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1579,7 +1579,7 @@ static void reg_bounds_sync(struct bpf_reg_state *reg)
static bool __reg32_bound_s64(s32 a)
{
- return a >= 0 && a <= S32_MAX;
+ return a >= 0;
}
static void __reg_assign_32_into_64(struct bpf_reg_state *reg)
--
2.27.0
Powered by blists - more mailing lists